Method and arrangement for providing information on multimedia options

ABSTRACT

A method and arrangement for providing updated information on the availability of multimedia options to terminal users. A first terminal (A) is initially engaged in a voice call with a second terminal (B) by using a first access admitting simultaneous multimedia communication. At least one available multimedia option is indicated based on capabilities of the first and second terminals. A change of connection is then detected from the first access to a second access not admitting simultaneous multimedia communication. In response thereto, a multimedia disabling notification is sent to the second terminal, and said at least one multimedia option is indicated as being no longer available. Preferably, the multimedia disabling notification is sent as an SMS message.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/721,644, filed Aug. 20, 2007, which was the National Stage ofInternational Application No. PCT/SE04/01951, filed Dec. 21, 2004, thedisclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to a method and apparatus forproviding information on the availability of multimedia options during acommunication session. In particular, the invention provides accurateindication of options to convey multimedia content such as video,images, text, etc, from one terminal to another.

BACKGROUND OF THE INVENTION AND PRIOR ART

Until recently, wireless mobile terminals have been used basically formaking voice calls. Standardised and well-established communicationtechnologies and protocols are then utilised to communicate voicebetween fixed and/or mobile terminals using circuit-switchedcommunication channels. However, a multitude of new multimedia telephonyservices are now rapidly being developed, enabled by the introduction ofnew technologies allowing for notably higher transmission rates andincreased network capacity. For example, GPRS (General Packet RadioService) and WCDMA (Wideband Code Division Multiple Access) technologiesare currently emerging for enabling wireless telephony servicesrequiring a wide range of transmission rates and different protocols andmedia formats.

Further, new sophisticated mobile terminals are also emerging on themarket, equipped with functionality to handle the new services,including high resolution colour displays and various codecs(coders/decoders) e.g. for handling visual information.

The trend today in the field of telecommunication is a move towardspacket-switched networks and technologies using the packet-basedInternet Protocol (IP), providing more capacity and flexibility ascompared to the traditional circuit-switched networks. Recently, anetwork architecture called “IP Multimedia Subsystem” (IMS) hastherefore been developed by the 3^(rd) Generation Partnership Project(3GPP) as an open standard, to give operators of access networks theability to offer multimedia services in the packet domain. IMS is aplatform for enabling services based on IP transport, more or lessindependent of the access technology used, which is basically notrestricted to any limited set of specific services.

Multimedia services typically involve the transmission of differenttypes of content such as text, documents, images, video and audio filesor “clips” in various formats and combinations. The term “multimedia”will be used in this description to represent telephony servicesrequiring the transfer of any choice of content, in addition to ordinaryvoice. Multimedia communication sessions typically involve combinationalservices with voice and other media at the same time.

It has been proposed that a multimedia session should be divided into acircuit-switched (CS) part for the voice transport, and apacket-switched (PS) part for the transport of other data incombinational services. In this way, the high performance associatedwith circuit-switching is obtained for voice, whereas not equallydelay-sensitive multimedia content can be adequately transferred bypacket-switching. New access networks typically allow for simultaneousCS and PS communication, such as WCDMA networks and GSM networks havingDTM (Double Transfer Mode) capability.

During a session between two terminals, certain session parametersdefining the rules of communication must be used by both terminals inorder to send and receive any desired information. Such sessionparameters may be related to available codecs, applications andmultiplexing schemes. Two communicating terminals may have differentcapabilities with respect to the above, and each terminal has initiallyno knowledge of the capabilities of the other. Hence, in order toestablish a multimedia session, session parameters that both terminalscan handle must therefore first be selected and determined by exchangingcapabilities.

A specification for session setup has been defined called “SIP” (SessionInitiation Protocol, according to the standard IETF RFC 3261 et al). SIPis an application-layer control (signalling) protocol for creating,modifying and terminating sessions over a packet-switched logic. In SIP,a method called “INVITE” is defined to initiate a session during a setupprocedure when the terminals basically exchange their capabilities.

Another method called “OPTIONS” is also specified in the SIP protocolallowing one terminal to query another terminal as to its capabilitiesregarding codecs and supported applications, without the user actually“calling” the other party. According to this method, the terminal sendsa capability query called “SIP OPTIONS”, preferably includes its owncapabilities, to the other terminal which then responds by sending overits capabilities. A “SIP OPTIONS update” message can also be sent ifthey are changed. In this way, both terminals will become aware of eachother's capabilities. The OPTIONS method can also be used during anongoing voice call for enriching the call with multimedia, provided thatboth access networks allow for packet-switched communication in additionto the currently ongoing circuit-switched communication.

By having knowledge of the other terminal's capabilities, each terminalcan determine which multimedia service and/or application options thatare available to their users, hereafter called “multimedia options” forshort, based on their mutual capabilities. A highly desirable feature isthat terminal users should be able to see on the terminal screen whichmultimedia options are currently available. Thus, after exchangingcapabilities each terminal may indicate the available multimedia optionsto their users on the terminal screen. Most commonly, associated iconsare then displayed but any other indication means may be used as well,such as other symbols, codes, texts, menu lists, etc. In this way, auser can easily select which type of service and media to use in amultimedia session with the other party.

For example, a multimedia option may be indicated as being available bythe mere presence of an associated symbol, icon, text or list entry onthe terminal screen, or by highlighting a displayed option by means of aspecific colour, light intensity, size, etc. An unavailable option maybe indicated by having a different colour, e.g. grey, light intensity orsize, or by being crossed-over, or simply by being deleted from thescreen. Thus, it is clearly understood that the availability andnon-availability of multimedia options can be indicated in manydifferent ways, and the present invention is not limited in thisrespect. In this description, the term “option indication” willrepresent any possible manner of indication.

When two terminals are engaged in a simple CS voice call, one of them(or both) may currently experience access constraints, such that a PSconnection is not admitted in addition to the ongoing CS call dependingon limitations in the access network. For example, a standard GSMnetwork cannot handle PS connections and CS connections at the sametime, although it may admit a PS connection separately. Some networks,including older GSM networks, may lack PS capability altogetheradmitting CS connections only. Further, one and the same network maycomprise certain geographic coverage areas admitting multimediacommunication, e.g. specific non-constrained cells, and also othercoverage areas not admitting multimedia communication, e.g. constrainedcells.

Modern terminals typically have the dual capability of executing a PSsession simultaneously with a CS call in order to provide combinationalservices. Furthermore, there are known mechanisms for a terminal tochange its radio access during an ongoing call, e.g. by moving from onecoverage area into another one. For example, some terminals are capableof both GSM access and WCDMA access by having dual radio parts.

Two terminals A and B may initially be prevented from establishing amultimedia session, due to access constraints for at least one terminalA having dual access capability. Terminal A may later, during theongoing call, obtain a new access allowing for an added PS part, e.g. bychanging from a standard GSM access to a WCDMA access or to a GSM/DTMaccess. When moving in the opposite direction, the terminals willexperience disablement of previously available multimedia options. Thus,when a communicating mobile terminal move between different types ofaccess networks, the prerequisites for multimedia communication mayconsequently change. This is a fact even if the other terminal isconnected to an access network allowing for multimedia communicationwith simultaneous CS and PS connections.

The International Patent Application PCT/SE2004/001671, filed Nov. 15,2004, discloses a solution for enabling multimedia communication duringan ongoing circuit-switched call. First, a mobile terminal uses anaccess having constraints by not admitting simultaneous PS and CScommunication. A change of connection is detected to another accessadmitting simultaneous PS and CS communication, and the terminalsexchange capabilities in response to the connection change. Then,possible multimedia options may be indicated to the users, e.g. on theterminal screens.

If the feature of displaying available multimedia options on terminalscreens is used in at least one of two communicating terminals, it is aproblem that the displayed options may become irrelevant as soon as anychange of access occurs for either of the terminals, due to constraintsin the new access. Thus, it is desirable to increase the accuracy ofthis feature.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a solution fordisplaying available multimedia options on terminal screens with greataccuracy during a multimedia communication session involving at leastone mobile terminal. It is another object of the present invention toupdate the displayed options in response to a change of access for themobile terminal.

These objects and others are obtained by a method and apparatus forproviding updated information on the availability of multimedia optionsto terminal users. A first terminal having a display screen is initiallyengaged in a voice call with a second terminal by using a first accessadmitting simultaneous multimedia communication. At least one availablemultimedia option is first indicated on the screen based on capabilitiesof the first and second terminals. When a change of connection isdetected from the first access to a second access not admittingsimultaneous multimedia communication, e.g. by the first terminal movinginto a different coverage area, a multimedia disabling notification issent over the second access to the second terminal in response todetecting the connection change. It is then indicated on the screen thatsaid at least one multimedia option is no longer available.

The first access may involve connection with a first access networkallowing packet-switched and circuit-switched communicationsimultaneously, and the second access may involve connection to a secondaccess network not allowing packet-switched and circuit-switchedcommunication simultaneously. The at least one multimedia option mayinvolve the communication of content including at least one of: a videoclip, an audio clip, a text, an image and a game.

The multimedia disabling notification is preferably sent as an SMSmessage, but may also be sent as a USSD (Unstructured SupplementaryService Data) message, or by means of user-to-user signalling. If SMS isused, the SMS message may comprise a standard SIP OPTIONS updatemessage, or a specific binary code that the second terminal canrecognise.

A multimedia option may be indicated as available by displaying anassociated symbol, icon, text or menu entry on the terminal screen, orby highlighting a displayed option by means of a specific colour, lightintensity or size. Further, when the at least one multimedia optionbecomes unavailable, it may be indicated accordingly by having adifferent colour, light intensity or size, or by being crossed-over, orby being deleted from the screen.

If a change of connection is later detected from the second access to athird access admitting simultaneous multimedia communication, e.g. bythe first terminal moving into another coverage area, a multimediaenabling notification is sent over the third access to the secondterminal. It is then indicated on the screen that said at least onemultimedia option has become available again. The multimedia enablingnotification may likewise be sent as an SMS message, or USSD message, orby means of user-to-user signalling.

The present invention further encompasses a mobile terminal adapted toprovide updated information on the availability of multimedia options toa terminal user. The invented mobile terminal comprises means for beinginitially engaged in a voice call with another terminal by using a firstaccess admitting simultaneous multimedia communication, and means forindicating at least one available multimedia option based oncapabilities of said terminals. The mobile terminal further comprisesmeans for detecting a change of connection from the first access to asecond access not admitting simultaneous multimedia communication, meansfor sending a multimedia disabling notification over the second accessto the other terminal in response to detecting said change ofconnection, and means for indicating that said at least one multimediaoption is no longer available.

As in the above-defined method, the first access may involve connectionwith a first access network allowing packet-switched andcircuit-switched communication simultaneously, and the second access mayinvolve connection to a second access network not allowingpacket-switched and circuit-switched communication simultaneously.Further, said at least one multimedia option may involve thecommunication of content including at least one of: a video clip, anaudio clip, a text, an image and a game.

The invented mobile terminal may be further adapted to send themultimedia disabling notification as an SMS message, or USSD message, orby means of user-to-user signalling. The mobile terminal may be furtheradapted to include a standard SIP OPTIONS update message in the SMSmessage, or a binary code in the SMS message that the other terminal canrecognise.

The mobile terminal may be further adapted to indicate a multimediaoption as available by displaying an associated symbol, icon, text ormenu entry on the terminal screen, or by highlighting a displayed optionby means of a specific colour, light intensity or size. The mobileterminal may be further adapted to indicate that the at least onemultimedia option has become unavailable by means of a different colour,light intensity or size, or by being crossed-over, or by deleting itfrom the screen.

The mobile terminal may be further adapted to detect a change ofconnection from the second access to a third access admittingsimultaneous multimedia communication, send a multimedia enablingnotification over the third access to the other terminal, and indicateon the screen that said at least one multimedia option is availableagain. The mobile terminal may be further adapted to send the multimediaenabling notification as an SMS message, or USSD message, or by means ofuser-to-user signalling.

Further features and benefits of the present invention will be apparentfrom the detailed description below.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in more detail by means ofpreferred embodiments and with reference to the accompanying drawings,in which:

FIG. 1 is a schematic view of a basic communication scenario where thepresent solution may be used.

FIG. 2 is a schematic view of a communication scenario where a mobileterminal A moves from one access network to another.

FIG. 3 is a signalling diagram illustrating a procedure for providinginformation on the availability of multimedia options on terminalscreens, in accordance with the present invention.

FIG. 4 is a schematic block diagram of a mobile terminal changing itsaccess from one network to another.

FIG. 5 is a flow chart illustrating a basic procedure for providinginformation on the availability of multimedia options, according to theinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 illustrates schematically a basic communication scenario betweena mobile terminal A and another terminal B, where the present solutionmay be used. Terminal B may be a mobile terminal, a wireless PC, or anyother communication unit, and both terminals are capable of multimediacommunication involving combinational services. Terminal A is currentlyin radio connection with a mobile access network 100, and each terminalA, B is equipped with a viewing screen S_(A) and S_(B), respectively,for displaying multimedia options, e.g. in the form of icons or theequivalent, as well as any received visual content. Of course, furthercommunication networks (not shown) may be involved in the communicationbetween A and B, and it is assumed that these terminals and networks arecapable of using conventional communication techniques and protocolswhich are not necessary to described here.

In FIG. 1, terminals A and B are engaged in a voice call 102, and theused networks, i.e. network 100 and others, allow for multimediacommunication and combinational services. It is assumed that theterminals have previously exchanged their capabilities which are thusmutually known, e.g. as described above. Accordingly, the multimediaoptions available within the capabilities of both terminals areindicated on the screens S_(A) and S_(B), as schematically illustratedat 104 and 106, respectively. This indication of options may be done inany manner, as discussed above. Hence, the users are free to activateany desirable application corresponding to an indicated availableoption, e.g. by clicking the associated indication on the screen, inorder to execute a multimedia session 108 involving the transfer ofmultimedia content.

An exemplary procedure in accordance with the present invention forproviding information on the availability of multimedia options on thescreens S_(A) and S_(B) of terminals A and B, respectively, will now bedescribed with further reference to the communication scenario in FIG.2, which is a continuation of the scenario in FIG. 1. The referencenumbers used in FIG. 1 will be used again for the same details in FIG.2. Thus, the starting point for this procedure is an ongoing call 102when available multimedia options 104, 106 are indicated on the screensof A and B.

During a first time period t₁ of the call 102, terminal A is connectedto a base station of a first access network 100 allowing for multimediacommunication with terminal B, as indicated with arrow 108. In thiscontext, it does not matter whether the terminals actually utilise anysuch option by executing a session 108 or not.

At some point during the call, terminal A moves away from the firstnetwork 100 and towards a second access network 200 not allowing formultimedia communication in this situation. For example, network 200 maynot allow for combinational services with simultaneous PS and CScommunication, or may lack PS capability altogether admitting CScommunication only. Network 100 may use WCDMA technology or GSM/DTMtechnology, whereas the new network 200 may use traditional GSMtechnology. A similar situation could also occur within the same networkif terminal A moves out of a non-restricted coverage area and into arestricted coverage area, e.g. between different cells in the samenetwork, and the present solution is applicable also in this case. Thus,networks 100 and 200 generally represent areas of different accesseswith respect to multimedia.

In the present case, terminal A is equipped with dual radio parts andcan therefore change its access from network 100 to the new network 200,even if they use different radio technologies. In order to do that,conventional intersystem handover procedures may be used, which are notnecessary to describe here further to understand the present solution.Thus, terminal A now becomes connected to access network 200, and thecircuit-switched voice connection between terminals A and B is stillcontinued over network 200 during a second time period t₂, as indicatedby arrow 202(t ₂).

However, since terminal A now experiences access constraints in network200, it has become impossible to enrich the ongoing voice call byintroducing multimedia in combinational services. Normally, this changeof access is conducted without being noticed by any of the terminalusers. Therefore, the user of terminal A, as well as the user ofterminal B, will not be aware of this sudden loss of multimedia options,unless they are notified in some way.

According to the present solution, terminal A is adapted toautomatically send a “multimedia disabling notification” to terminal Bin response to detecting a change of access not allowing for multimedia,in this case access to the new access network 200. As terminal Breceives the multimedia disabling notification, it becomes aware thatthe previously available multimedia options are no longer available.

Moreover, both terminals can now change their indication of options 104and 106 by indicating the options as unavailable instead, which isillustrated in the figure at 204 and 206, respectively, in response tothe access change of terminal A. As mentioned above, the indicationwhether multimedia options are available or not can be made in anysuitable manner, and the present invention is not limited in thisrespect. In this way, each user of terminal A and B will immediately beaware of the new communication restrictions by viewing his/her terminalscreen.

According to a preferred embodiment, the multimedia disablingnotification is a standard SMS (Short Messaging Service) message thatthe receiving terminal B can recognise. According to one alternative,the above-described “SIP OPTIONS update” message may be included in theSMS, substituting a regular SIP OPTIONS update message over IP, sincethis has become impossible to convey over the new access. However, theSMS may basically be any binary code that B can recognise, notnecessarily being intelligible to humans, but may also be a specificalphanumeric combination. According to other alternatives, themultimedia disabling notification may be sent as a USSD (UnstructuredSupplementary Service Data) message, or by means of “user-to-usersignalling” directly between the terminals embedded in the establishedvoice channel or in a suitable control channel, e.g. according to thestandard 3GPP TS 23.087.

With reference to a signalling diagram illustrated in FIG. 3, anexemplary signalling procedure will now be described for executing theinventive method basically according to the scenario of FIG. 2. Thediagram thus includes the mobile terminals A and B, the first accessnetwork 100 having no access constraints, and the second network 200having access constraints. The access network used by terminal B is notshown, but it is assumed that terminal B does not experience any suchaccess constraints in this context. It should be noted that the mobileterminals A and B could be any communication units capable ofsimultaneous PS and CS communication.

In a first step 300, terminal A gains access with the first network 100,e.g. when powered on. A next step 302 illustrates that acircuit-switched voice call between terminals A and B is established. Itdoes not matter which one of A and B is the calling party and calledparty, respectively.

In a step 304, the terminals A and B exchange their capabilitiesaccording to any standard procedure, e.g. using a SIP OPTIONS message,in order to determine any available multimedia options during this call.Next, these are indicated on the screen of terminal A in a step 306 andon the screen of terminal B in a step 308. It should be noted that anynumber of multimedia options may be displayed depending on the terminalcapabilities, and the present invention is not limited in this respect.The terminal users are now free to activate any application offered bythe indicated available options, e.g. by clicking a selected optionindication on the screen, to enrich the ongoing voice call byintroducing multimedia in a parallel session 108, as indicated in anoptional step 310.

At some point later during the call, terminal A performs an intersystemhandover to the second access network 200, in a next step 312. Sincenetwork 200 imposes access constraints to terminal A by not allowing forcombinational services with multimedia communication, the indicatedavailable options are no longer relevant. Therefore, in accordance withthe present solution, terminal A sends the above-described multimediadisabling notification in a step 314 that terminal B will recognise,preferably as a specific SMS message, or USSD message, or by means ofuser-to-user signalling.

As both terminals are now aware of the disablement of multimedia, theoptions are indicated as being unavailable on the screen of terminal Ain a step 316 and on the screen of terminal B in a step 318. Asmentioned above, this can also be done in different ways, for example bychanging colour (e.g. to grey), light intensity or size, or by beingcrossed-over, or simply by being deleted from the screen. In any case,the terminal users can now easily see that the options are no longeravailable, and the availability indication will always be up-to-date. Atthe same time, the voice call may continue over network 200 in a finalstep 320, without being affected by the above-described activities.

A possible procedure of detecting the above-described change of accessby terminal A will now be described in more detail with reference toFIG. 4, which is a schematic block diagram of the logic structure ofterminal A. In terminal A, specific logics are implemented for handlingthe radio functions and service functions, as represented by logic units400 and 402, respectively. In this case, radio logic 400 is capable ofhandling radio access with both networks 100, 200. Each logic 400, 402comprises a protocol stack according to the prevailing standards, notdescribed here further. Of course, there are other logic systems (notshown) implemented as well in the terminal for other functions, whichare not relevant to describe here.

Above the service logic 402, a series of applications a1, a2, a3 . . .are installed in order to enable various services, as controlled by theservice logic 402. For example, one application a1 may be used forplaying a video file in a specific format using a corresponding codec,whereas another application a2 may be used for displaying a picture in aspecific format, as received from the other terminal B, using anothersuitable codec, etc. Each application a1, a2, a3 . . . may be associatedwith an option indication 406 on the terminal screen, and the indicationof available options implies that the corresponding applications can beactivated by the user.

When terminal A makes an intersystem handover from network 100 tonetwork 200, the radio logic 400 notifies the service logic 402 by meansof an internal message 408. The service logic 402 then orders the radiologic 400, by means of an internal message 408, to send theabove-described multimedia disabling notification towards terminal B.Then, the multimedia disabling notification 412 is issued accordinglyfrom the radio logic 400 over the new network 200, corresponding to step314 above.

Referring to a flow chart in FIG. 5, a basic procedure of providinginformation on multimedia options according to the present solution willnow be described. This procedure is executed in a mobile terminal, suchas terminal A shown in FIGS. 1, 2 and 4. In a first step 500, the mobileterminal gains a first access, e.g. with network 100 above, and starts avoice call with another terminal using said first access. The firstaccess allows for multimedia communication, e.g. by means ofsimultaneous PS and CS communications.

In a next step 502, the mobile terminal exchange capabilities with theother terminal in order to determine any available multimedia optionsduring the call. Next, the available options are indicated on the screenof the mobile terminal in a step 504, which also can be indicated on thescreen of the other terminal as well. Thereby, the terminal users canselect any of the available options and execute a multimedia session, asindicated by an optional step 506.

At some point later during the call, a change from the first access to asecond access is detected in a next step 508, e.g. by making anintersystem handover as described above. Thereafter in step 506, it isdetermined whether the new access allows for multimedia communication byadmitting packet-switched communication simultaneously with the ongoingvoice call. If so, the voice call and multimedia session can continuewithout further action, according to step 512. However, if the secondaccess does not admit a multimedia session, the mobile terminalautomatically sends a multimedia disabling notification to the otherterminal, as indicated in a step 514.

Next, the options are indicated as unavailable on the screen of themobile terminal in a step 516, which also can be indicated on the screenof the other terminal as well. Thereby, the availability of multimediaoptions will be automatically updated on the screens. Alternatively, thedetected change of access in step 508 may be a new access obtainedwithin the same first network, e.g. by making handover from onenon-constrained cell to another constrained one not admitting multimediacommunication.

If the mobile terminal later gains a new access allowing for multimediacommunication, e.g. by returning into coverage of the first network 100in FIG. 2, the multimedia options can be indicated as available again.Thus, if terminal A generally gains a third access allowing formultimedia communication during the still ongoing voice call, terminal Amay send to terminal B a new “multimedia enabling notification” over thenew access that terminal B will recognise. This message may likewise besent preferably as a specific SMS message, or USSD message, or by meansof user-to-user signalling. Also, the options can then be indicated asavailable again on the screens of the mobile terminals. In this case, noterminal capabilities need to be exchanged again, but the same optionsas before can be indicated, assuming that the terminals have not changedin this respect. Alternatively, the terminal capabilities can beexchanged once again, e.g. according to the mechanism disclosed inPCT/SE2004/001671, which however lies outside the scope of the presentinvention.

It should be noted that the existing SMS mechanism in particular isquite suitable for conveying the above-described multimedia disablingand enabling notifications between terminals, regardless of whether thecurrent access allows for multimedia or not. Thus, the SMS functionalityshould be regarded as an available means for communicating thenotifications over any of the first, second and third accesses in thedescribed embodiments.

The present invention will thus provide the terminal users with updatedinformation on the availability of multimedia options, even if one ofthe terminals change access during an ongoing voice call. Thereby, thefeature of displaying such options on the terminal screen will beenhanced by increased reliability.

While the invention has been described with reference to specificexemplary embodiments, the description is in general only intended toillustrate the inventive concept and should not be taken as limiting thescope of the invention, which is defined by the appended claims.

1. A method of providing updated information on the availability ofmultimedia options to terminal users, said method comprising: wherein afirst terminal having a display screen is initially engaged in a voicecall connection with a second terminal by using a first radio accesswherein said first radio access supporting simultaneous multimediacommunication for said first terminal, and at least one multimediaoption supported by said simultaneous multimedia communication, said atleast one multimedia option supported by said simultaneous communicationis available when using said first radio access, is indicated on thescreen based on capabilities of the first and second terminals,detecting a connection change from the first radio access to a secondradio access for providing said voice call connection, detecting, bysaid first terminal, that said second radio access cannot support atleast one multimedia option, sending, from said first terminal to saidsecond terminal, a multimedia disabling notification over the secondradio access to the second terminal in response to said detecting step,wherein the screen of said second terminal indicates that said at leastone multimedia option is no longer available from said second radioaccess.
 2. The method according to claim 1, wherein the first radioaccess involves connection with a first access network allowingpacket-switched and circuit-switched communication simultaneously, andthe second radio access involves connection to a second access networknot allowing packet-switched and circuit-switched communicationsimultaneously.
 3. The method according to claim 1, wherein said atleast one multimedia option involves the communication of contentincluding at least one of: a video clip, an audio clip, a text, an imageand a game.
 4. The method according to claim 1, wherein the multimediadisabling notification is sent as an SMS message, or a USSD message, orby means of user-to-user signaling.
 5. The method according to claim 4,wherein the SMS message comprises a standard SIP OPTIONS update message.6. The method according to claim 4, wherein the SMS message comprises abinary code recognizable by the second terminal.
 7. The method accordingto claim 1, wherein a multimedia option is indicated as available bydisplaying an associated symbol, icon, text or menu entry on theterminal screen, or by highlighting a displayed option by means of aspecific color, light intensity or size.
 8. The method according toclaim 7, wherein in said indicating step, said at least one multimediaoption is indicated as unavailable by having a different color, lightintensity or size, or by being crossed-over, or by being deleted fromthe screen.
 9. The method according to claim 1, wherein, if a change ofconnection is detected from the second radio access to a third radioaccess wherein said third radio access capable of supportingsimultaneous multimedia communication, a multimedia enablingnotification is sent over the third radio access to the second terminal,wherein it is indicated on the screen that said at least one multimediaoption is available again.
 10. The method according to claim 9, whereinthe multimedia enabling notification is sent as an SMS message, or USSDmessage, or by means of user-to-user signaling.
 11. A mobile terminaladapted to provide updated information on the availability of multimediaoptions to a terminal user, comprising: means for being initiallyengaged in a voice call connection with another terminal over a firstradio access wherein said first radio access supporting simultaneousmultimedia communication for said mobile terminal, and means forindicating, based on capabilities of said terminals, at least onemultimedia option available when using said first radio access; meansfor detecting a change of connection from the first radio access to asecond radio access for providing said voice call connection, means fordetecting, by the mobile terminal, that said second radio access is notcapable of supporting at least one multimedia option; means for sending,from said mobile terminal to said other terminal, a multimedia disablingnotification over the second access to the other terminal in response todetecting said change of connection; and wherein the screen of saidsecond terminal indicates that said at least one multimedia option is nolonger available from said second radio access.
 12. The mobile terminalaccording to claim 11, wherein the first radio access involvesconnection with a first access network allowing packet-switched andcircuit-switched communication simultaneously, and the second radioaccess involves connection to a second access network not allowingpacket-switched and circuit-switched communication simultaneously. 13.The mobile terminal according to claim 11, wherein said at least onemultimedia option involves the communication of content including atleast one of: a video clip, an audio clip, a text, an image and a game.14. The mobile terminal according to claim 11, wherein the mobileterminal is further adapted to send the multimedia disablingnotification as an SMS message, or USSD message, or by means ofuser-to-user signaling.
 15. The mobile terminal according to claim 14,wherein the mobile terminal is further adapted to include a standard SIPOPTIONS update message in the SMS message.
 16. The mobile terminalaccording to claim 14, wherein the mobile terminal is further adapted toinclude a binary code in the SMS message that is recognizable by theother terminal.
 17. The mobile terminal according to claim 11, whereinthe mobile terminal is further adapted to indicate a multimedia optionas available by displaying an associated symbol, icon, text or menuentry on the terminal screen, or by highlighting a displayed option bymeans of a specific color, light intensity or size.
 18. The mobileterminal according to claim 17, wherein the mobile terminal is furtheradapted to indicate that said at least one multimedia option has becomeunavailable by means of a different color, light intensity or size, orby being crossed-over, or by deleting it from the screen.
 19. The mobileterminal according to claim 11, wherein the mobile terminal is furtheradapted to detect a change of connection from the second radio access toa third radio access, wherein said third radio access capable ofsupporting said simultaneous multimedia communication, send a multimediaenabling notification over the third radio access to the other terminal,and indicate on the screen that said at least one multimedia option isavailable again.
 20. The mobile terminal according to claim 19, whereinthe mobile terminal is further adapted to send the multimedia enablingnotification as an SMS message, or USSD message, or by means ofuser-to-user signaling.
 21. The method according to claim 10, whereinthe user-to-user signaling is direct between the terminals and isembedded in the established voice call connection.
 22. The methodaccording to claim 10, wherein the user-to-user signaling is directbetween the terminals and is embedded in a suitable control channel.